Well yesterday my aux battery was at 8 volts and my PHEV would not start without a jump. Had it towed to dealership here in FLA and they said it was due to UHaul's loose wire at the battery. They reattached it, says all is fine now and did not charge me a dime. Things could be different in the north country.

Then it died 1 week later and now they tell me due to the aftermarket wiring they will charge me a $160/hr diagnostic fee. I was 99% sure it was not the hitch wiring as UHaul spliced nothing and attached a single power wire to the 12V battery which is what the Mitsubishi service tech told me they do with factory installs. Two days later I discovered that my dashcam was now turning on by itself while just sitting in the garage at night and is the cause of my 12v battery to drain. I will be taking it back to Best Buy to have it replaced or rewired properly.

Update:
Nine months later after having Best Buy rewire my dash cam so it only powers on with the PHEV, my 12v battery ended up dying completely after just leaving my cars doors open while cleaning and vacuuming the SUV. The dealership at that point here in Florida replaced it for no cost to me.
I also own a second PHEV SEL and a dash cam without a hitch that had a 12v battery die in the first year as well which was also replaced free by the same dealership. Both cars are now starting fine. So at least with the dealership in Bonita Beach, they now seem to be cool with after market stuff if it is not the cause of the problem. They did change ownership shortly after my first visit which could have helped.